I. Field of the Invention
This invention relates to surgical instruments for introducing fluids into a cavity of a body. It has special utility in the simultaneous introduction of non-compatible fluids, particularly those that are non-miscible and those having different viscosities.
II. Description of the Related Art
A catheter is a tubular medical device that is inserted into vessels or body cavities to permit the injection or removal of fluids or substances or to maintain open a passageway within a body of a patient. The term "patient" is used to include animals as well as humans. In the past, catheters have been provided with one or more lumens, which are elongated tubes that are incorporated within the body of a catheter and extend in the form of a tube or a hollow needle.
One type of catheter used in the prior art is known as a central venous catheter. This type of catheter is generally inserted into the subclavien vein or the external jugular vein, all located within close proximity of a vital organ such as the chest and heart. Usually the central venous catheter is a long cylindrical tube approximately 20 to 30 centimeters (8 to 12 inches) long and has a diameter of approximately 0.3 centimeters (1/8 inch). One type of central venous catheter is known as a tri-lumen central venous pressure line. Such a pressure line contains 3 lumens, each of which extends from an extended diaphragm to a trifurcation member where the 3 lumens are held together. Fluid of a unique characteristic desired to be imparted or injected into an individual patient is applied using a syringe to inject a different unique fluid into each of the 3 diaphragms. The 3 different fluids enter a respective lumen for further movement of the respective fluids towards their points of discharge into the body of the patient. Each lumen has a discharge point at different distances from the trifurcation point. The lumen that discharges fluid into the patient's body at the closest point to the trifurcation point is called "the proximal discharge point", the lumen having a middle discharge opening is termed "the medial discharge point" and the lumen whose discharge point is at the greatest distance from the trifurcation point is termed "the distal discharge point".
In prior art devices, the individual lumens had to be of sufficiently large cross-section to provide injection of 3 different fluids at 3 different spaced positions within the body of the patient. It was believed necessary to provide such injections in the vicinity of the large blood vessels near the heart and other vital organs of the patient. Such proximity to the vital organs rendered the insertion of catheters a dangerous job, which made it necessary that a highly trained and highly skilled person, such as a doctor, had to perform the insertion of the catheter.
Double current catheters suitable for removing blood from a fistula or vein for processing in a dialysis machine and returning the processed blood back to the fistula or vein is disclosed in U.S. Pat. No. 4,134,402 to Mahurkar. Another double lumen catheter provided with additional features to promote insertion and to perform a dilator function is disclosed in U.S. Pat. No. 4,568,329 to Mahurkar. The patents to Mahurkar disclose double lumen continuous flow hemodialysis needles and cannulae having contiguous lumens of different lengths formed by dividing a unitary straight tube with an internal longitudinal septum. The shorter lumen acts as a blood intake lumen and the longer lumen acts as a blood return lumen. In the Mahurkar patents, the catheters are divided into semi-circular lumens of equal cross-section extending side by side for a major portion of the length of the catheter. In only a short portion at the distal end of the catheter do the lumens have different cross-sections.
Numerous other United States patents disclose double current catheters for hemodialysis that evidence a long felt need for a small, functionally efficient catheter, having a minimum of insertion trauma and potential for clotting. U.S. Pat. No. 4,096,860 to McLaughlin discloses a coaxial hemodialysis catheter said to allow a step enlargement of the opening of a blood vessel to avoid its tearing and rupture along its side walls. A simultaneous flow device incorporates a hub with an extension conduit and a valve to receive a needle therethrough. The extension conduit is sufficiently large to allow the needle to pass therethrough adjacent the interior side walls with an attendant extension thereof from its opening. The needle with the extension conduit is adapted for combined insertion within a blood vessel, after which it can withdrawn while the valve prevents the backflow of blood through the axial passage of the hub. A coaxial flow device can then be inserted within the hub conduit.
U.S. Pat. No. 4,099,528 to Sorenson et al discloses a coaxial double lumen cannula mounted upon a hub and having a central stylet needle to penetrate a patient's vein and which is retractable after penetration. This patented technique is a standard procedure for inserting catheters and is commonly termed the "over the needle" tecchnique.
U.S. Pat. No. 4,203,436 to Grimsrud discloses a hollow hypodermic needle with a divider to provide a first channel to remove blood for treatment from a punctured blood vessel and a second channel to return the treated blood to the blood vessel.
U.S. Pat. No. 4,385,631 to Uthmann discloses a hemodialysis catheter to puncture blood vessels. The Uthmann device includes a section insertable through a puncture opening into a blood vessel and a hose line following thereafter.
U.S. Pat. No. 4,403,983 to Edelman et al discloses a dual lumen cannula in the form of a tube divided longitudinally throughout essentially its entire length by a septum to create two parallel lumens at equal cross-section, one for withdrawing blood from the subclavian vein for extra corporeal processing and the other to return the treated blood back to the subclavian vein in the area of blood withdrawal.
U.S. Pat. No. 4,180,068 to Jacobson et al discloses a double current hemodialysis catheter comprising a primary tube and an internal divider which also functions as a trocar and valve. The primary tube has a side opening to receive blood and a central opening at the distal end of the primary tube. The internal divider includes a cutting end which protrudes from the distal opening when the divider is longitudinally moved to an insert position. In the insert position, blood flow is blocked.
U.S. Design Pat. No. 272,651 to Mahurkar discloses a double lumen catheter having an outlet lumen which has an opening at the tip of the catheter and a shorter inlet lumen which terminates in a bevel substantially displaced from the tip of the catheter.
None of the patents described provide a catheter having a cross-section sufficiently small to encompass a plurality of small cross-section lumens which are capable of insertion into a peripheral portion of a patient's body such as the arm or leg of a patient so that different fluids which are non-miscible with one another can be applied in spaced relation within the patient's body using peripheral venous catheters, while maintaining integrity and independence of each of a plurality of injected fluids or medications being simultaneously applied to the patient.